Telegraph system



Patented June 17, 1930 UNITED STA-'res '.PATNT-f Voiffrici:

HOWARD L. AND JOHN 0. CARR, OF CHICAGO, ILLINOIS, ASSIGNORS,'BY MESNE ASSIGNMENTS, TO TELETYPE CORPORATION, OF CHICAGO, ILLINOIS, A' CORPORA.-

` 'non oF DELAWARE f 'rnnnenarnjsysrmr j vprppiimizion med August 23, 1922, serial No( 583,718. Renewed lnay i1, 192s.

Our invention relates generally to tele-V graph systems, and more particularly to printing v in synchronously'operated transmitting and receiving distributers are employed.

yOne object of'our invention is to provide novel means for' controlling ythe electric'.

motors Which`drive the distributers. In

prior systemsa control of the motorhas' been obtained by varying the load, or .by vvarying the circuit of the armature or field of the motor, or both. In many of these prior systems, much time is required to 'get the lsystems into operation. By our arrangement the motor is supplied with both alternating eurent and direct c'urrent, and

When'it liasbeen brought up to speed by the direct current, it operates in some .re--

spects at least -as a' synchronous motor. With our arrangement We' are able to `place the system in operating condition in a very short time.v Y j Another object of our` invention is to provide the vibrating member by which the al ternating current is supplied to the motor of the corrected' distributer, With a new con# trol. For this purpose We employ ltvvo electromagnets, one of which isenergizedA intermittently, and the otherfof which is energizedby continuous but varying current. There are novel features in the joint operation of these controlling elements and in their sole operation in combination with other parts of thesystem. j

Another object of our invention is to provide anovel adjustment Aof the receiving distributer contacts so that the operating' contact associated with-the signal :-'re ceiv.

ing contacts and corresponding'to the` k p" Aating impulse which follows" the signi-tlf` pulses, bears arcons'tant and unchangingiea lation to the signal-.receiving contactssjand@ 'yetfan adjustment'. is had by which thellatter j j 'fand casinglof the receiving distributer.v y 1 n receive lthe incoming impulses. mosteiie'v tacts of the receiving distributer. A further object of ourinventionto provide novel indicatingmeans for making telegraph and like systems Where-g "'Stl'llCted' alldffarra'nged in accor thepresentiiivention.

' maybe adjusted with ments of the yhead.

known the relative speeds of the correcting andl corrected vrdistributers. y embodiment'signal lamps are connected to special indicator contacts on the head of the v. correctedfdistributer andthe associated traveling means, Whether a brush or contacts -otherwise`- operated, applies impulses re! ceived from` the correcting distributer insuoh' away that'the'o'peration of the lamps shows whichl distributer is traveling the sidesinjtheindicating means itself and in ed i faster and how much faster. .1 Novelty reits combinationV with other parts of the sys tem. j

A still further object of .our invention vis `to so arrange the parts of the systenithat the normal currenton theli-ne when running 1d le,` that 1s,.when sending blank 'signalsl Wfill give frequent 'polarity reversals for correction purposes and sothata modification yof the same-'normal current maybe used in operating the :indicating means; lvTo .this

'end'fwe preferablynormally'send a purev alternat'ing current to line.- Its?` reversals of polarity assure frequentjcorrections, and by switching out everyl other Wavea,4 pulsating current ofy regular frequency is indicating purposes.

Thev above :and other objects andfeatures; i I offour invention will 'be more fullyiunder- `stood 'upon reference to the following de` tailed descriptionytaken in connection `v vith the accompanyingdrawing,'jwherein We dis'- i close apreferredfembodimentiof our invention, While thfezscope Vof our invention will bewparticularly set inthe-appended .Y

diagram of a printing telegraphs stein vcon- Fig. 2 is a face view of the' contact headl Fig.f3v isa sideelevation of the same.

i Fig. '4 isy asection'al detail View showing. l Particularly howthe correcting-,Segments reference to other seg-` Figl 5:isajvievvyillustrating diagramj,100` l obtained for seven stages or conditions of the indicator lamps and their associated distributer contacts, arranged to illustrate how vthe lamps indicate the relative speeds of the correcting and corrected distributers.

' Fig. 6 's a side view ofa portion of then tuning fork used in the .control of the motora which drives the receiving distributer, inaswhich are operated in various code'combina- `t1ons 1n accordance with the signal to be transmitted; B the developed segmental contacts of the transmittingdistributer head and theirasso'ciated brushes C the motor by which the transmitting dstributer is driven; ,D the mechanism f orfcontrolling the application of alternating current to' motor- C; E the bank of recetvingrelaysgf-Fthe de-Y veloped segmental passive contacts of thereceiving distributor; G'thedmotor for driving the receivingdistributhr'; H the mechanism for controlling the application 4of alternating current to the motor G; I Athe motordriven rheostat which controls theA current flow through one of the windings ofthemotor' ftran-'smitting control mechanism H; and J a series of associated rela-ys which includes the line relay LR, the printing relay PR, the switching relay SR, the correcting relay CR, the motor relay MR, and the holding relay HR. These various parts constitute the equipment at each station upon the line L. In the diagram the latter is shown by a broken line 'to indicate that it extends to alstation ata distant point. The only equipment of the second station'which is shown is the line relay LR and some of its connections, 'but it is to be understood that the other partsmentioned are to be found at the distant station also.

For the purpose of illustrating our invention, we have shown a system intended for use with the Baudot code, although it will be understood that the same may be modified to meet the requirements of other similar codes. According to the Baudot code, there are five current impulses or signal intervals for each character or signal, and each set of tive impulses is followed by a single impulse, not necessarily sent over the line, for performing some additional function such asorating the prirter magnet. At this point it maybe well to mention also that theinvention is shown in a system employing a line. It will be obvious from the present description, however, that the inventionis applicable also. to wireless systems whereinv current waves are transmitted than a telegraph wire. In such case the line conductors would give placeto aerial conductors. It will also be apparent that many of the features of the invention willl be applicable in wholly different environments than herein set forth.

We may now consider the contact bank A and the contacts of the associated transmitting distributer B. The transmitter contact bank A, being designed for the Baudot code, includes-a set of five contacts 10. These contacts are supplied with current from supply mains 11 and 12 through leads 13 and 14 controlled by a switch 15. When the switch 15 is closed, the first, third and-*fifth contacts 10 are 'connected to the positive main 11, and the intermediate conf tacts 10, viz: the second and fourth, are connected to theA negative main A12. -When moved totheir alternate positions, the first, third. and fifth contacts 10 are connected to the-.negative main 12, and the second and fourth are connected to the positive main AA11A'. 'With this arrangement it will be seen that the marking impulses of the first, third and fifth contacts 10` are negative, and the marking impulses of` the second and fourth contacts l0v are positive. The set of contacts 10 are permanently connected by a se- .ries of y conductors. 16 to five' segmental contacts 17 for-min part of the transm1tte'r"`"distributer hea. These connect-ions are such that when the brush 18 passes over thev contacts 17 `they successfully bring the contacts 10 into circuit'and- 100 ed conductor 20'. -In the present instance the system is arranged for' two channel Work and, therefore, the segmental contacts 17 are duplicated in the contacts-17 and the conductors 16 are duplicated in lthe conductors 16. In the case of the'transmitting contacts of the second channel, we

employthe same arrangement asin the case 110,'

of the first channel but interchange the connections to the supply mains -11 and 12. In other words, whereas in the first chan-l nel, lead 13 is connected to main 11, We connect the lead 13 of the second channel 115 throu h switch 15" to the negative main`v 12. imilarly, whereas in the first chan-y nel, lead 14 is connected to the negative main.12,'\ve connect the lead 14 of `the'sec- 7 ond channel to the positive main 11. As a result of this arrangement, a pure alternating currentl is supplied to the conductor 20 Whenever the transmitter is allowed to run idle with the switches 15 and 15 closed.v

This means that as the brush 1S passes over 125 the contacts 17 and 17 the current impulses passing through the first channel will be successively positive, negative, positive, negative, positive, and that the current imthrough the air, or ether, or other agency pulses immediately following through the a pure alternating current is supplied to the line as long as the transmitting distrib-` uter continues Ato run idle. Besides lthe transmitting segmental'contacts 17, 17', and

ring contact 19, with their associated brush 18, there are the localsegmental contacts 21 and 21 co-operating with a ring contact 22 by means of brush 23 to close a ci cuit through the transmitter operatinor m net 24, the circuit being completed ijrom attery 25. YVhen'ever the brush 23 engages contact 21, the magnet 24 will be operated to perform some function in connection with the transmitter, suchas releasing the actuated keys of a keyboard transmitter, in case such is employed, or to cause the advance of the tape, in case a tape transmitter is employed. lt will be-.understood that the contacts 10 may be operated in either of these Ways, such mechanism being common and well known in the art. The segmental contact 21 is positioned so as to close its circuit just after the circuit has .been closed through the last of the transmitter contacts 10. Thus intransmitting, the five current impulses applied to the conductor 2.0 are followed by a local impulse through the magnet 24. Just as tlielocal magnet 21 is associated with the transmitting contacts 17 Vof the first channel,`so the local contact 21 is associated with the transmitting contacts 17 of the second channel, and controls a magnet similar to the magnet 24.

le may now consider the 'motor C and its. controlling mechanism D. The motor C is provided with' a ield'winding25 which vis connected by leads 26 and 27 through switch 28 to the supply mains 11 and 12. A path, in parallel to the ield winding 25, extends from lead 27 through the commutator 29 the direct current wiiiding'of the motor armature and back through the commutator 29 to one terminal of the resistance 30 of the rheostat 31, the arm 32 of which is connected to the lead 26. The winding. 'of motor armature is also provided with' alternating current taps or, if desired, an-

additional alternating current winding connected to the collecting rings 33 and 34, and the latter are included in circuitby means of conductors 35 and 36 withthe terminals of a secondary winding' 37 of a transformer 38. A lamp 39 is included in thisV circuit. The primary windings 40 and 41 ofthis transformer are connected atan iii- A termediate point to'ground and at their reniote terminals to conductors 42 and 43, re-

s'pectively; The latter.` terminate in contacts whichco-operate with a vibrating contact 44 mounted upon one "arm of the fork 45 of the controlmechanismfD. yThe fork 45 is mounted on a suitable base so as to leave its vibratingends yfree .for .n vibration, and

its `fixed endis connected in circuit witha battery 46. As the fork 45 vibrates, the contact 44 connects alternately 'with conductors 42 and 43 and thereby supplies a current, first, through Winding 40 1n one direction,

and then throughjwinding 41 in the oppo- 'l tory circuitwith contact 49. This circuit' An iay be traced from the live pole of battery 46 through fork 45, contact 49, and the winding of magnet 48 to ground.` By plucking the ends of the fork `the same 'may 'be set in vibration, and as it vibrates the vibratory circuit will be alternatel 'made and broken at contact 49 to maintain thejfork vibrating. The magnet 48 is positioned between the tines of the fork and its pole faces are adjacent to the same in order to draw them together --when the magnet is energized,

and allow .them to spring apart whenl it is deenergized. In starting the motor C, the switch' 28 is so as to supply direct current to the field 25 'and the directcurrent winding of the armature.v Then the fork is set vibratingl and the arin 32 of the rheostat 311is manually 'moved until the indicator lamp 39 burns steadily. With this arrang'einentthe source of current.46,'under the control of the fork 45 andthe transformer 38, supiplies alternating current to the motor C, and causes Ait to operate in part at least as a synchronous motor. This alternating current source, however, is not quite suiicient to run the motor of itself4 and, accordingly,

the direct current source is used to supply,

the additional energy required to properly drive the motor. Likewise, the direct current supply is' used to bring the motor up to speed, in order that the same may operate lsynchronously with the alternating. current suppliedl We may now consider the bank E of receiving relays and the associated receiving contacts of -the developed v segmental contacts F of the,receivingdistributen It will AA first closed ion ifo

.be noted that the signal'. impulses which are appliedH to the lconductor 2O will pass tliroughthe two windings of the line relay LR in parallel, one path leading through the artificial line 50 andthe other through the line L, 'and the windings of the distant relay LR and' the artificial line 50 in series.,

Since ythe line relays LR and LR". are differential relays,`tlie circuit thus traced will not operate relay LR but Will operate relay' L R. Likewise, if .the transmitter at the dlstant station be employed, it will send impulses through conductor dividing at relay LR", part going to ground through the ,artificial line 50', and the other part passing.

through the line L, the windings of line LR in series, and the artificial line 50 to ground. Assuming that the impulses are coming from the distant station and that the transmitter contacts l0 at that station are in the position shown, then it will be apparent that the signal receiving relays 51 of the bank E will not be operated. Thus, thepath of the first impulse we may trace from positive Ysupply mainll through lead 13, normal contact 10, segmental contact 17, brush 18, ring contact 19, all at the distant station, then through conductor 20', line L, line relay LR, and artificial line to ground. Theapplication of current by the closing of this circuit will cause relay LR to shift its tongue 52 to the left, and this will close a circuit from battery 53 through the windings of printing relay PR to ground. Rela PR will then shift its tongue 54 to the le t and thus disconnect conductor 56 and the segmental receiving contacts 55.` Consequently, as the brush 57 passes over the first contact 55,'no current will beapplied to the first signal receiving contact 58 and, consequently, no current will flow through the first receiving magnet 51. Similarly, acircuit through thel second transmitter contact 10 may be traced from the negative supply main 12 through leadflfl, Athe second normal windings of relay PR to ground. Relay PR will then shift itstongue 54 to the right and thereby ldisconnect conductor 60 (at this time continuous througliclosed swltch 61) 4. andthe multiply connectedcontacts 62,in

terposed between contacts 55 in the path of travel of brush 57. Since the first contact 62 is disconnected at the time the brush 57 passes over the second contact 58, the second receiving magnet 51 will not beV operated. In a similar manner, the circuits for each of the succeeding contactsA 10 of the transmitter may be traced. `From the "tracing of these circuits we see that while the transmitter contacts are in their ntrmal position, there is no'current flow thrdiigh the receiving magnets 51. However, it mejor the contacts 10 be moved to its alter l te position, then it will be seen that the e ectrical connection will be reversed relativ A gothat just traced, and the line relay LR-"`will move oppositely to the way just pointed out, withv the result that the printing relayfPR, which ting station, conductor 20, line L, line relay LR to ground. The polarity of this current will cause 'relay LRv to shift or hold its 80' tongue 52 to the right and thus close. a circuit for relay PR which will cause its tongue 54 to occupy the same position. Conse' quently, a circuit will be completed from battery 63 through tongue 54 and conductor 35.

56, to segmental contacts 55. Then as b rush 57 passes over contacts 55 and 58, the circuit will be continued through the first receiving magnet 51 and cause its operation. From the tracing of this circuit it will be appar- 9o' eut that when other transmitter contacts 10 are moved to their alternate positions other l corresponding receiving relays 51 will be operated. The operation of these relays will,

through suitable mechanism, set up the let-- ter` or symbol corresponding to theparticular combination of impulses sent over theline. In addition to receiving the five signal impulses through its magnets 51, the

operating magnet 64 of the receiver will re- 100 ceive an additional or sixth impulse through segmtntal contact 65, as the latter is brought by brush 66 'into connection with ring contact 67 which, in turn, is connectedto the live pole of battery 68. This sixth impulse 155 operates the magnet 64 to perform some desired function in connection wlth the printer, such as operating the printing magnet.

-As shown, the contact 65 is associated with v the first channel and a. similarl Contact 65 110 is associated with the second channel. Similarly, the contacts 58 are associated with the first channel and contacts58 with the second channel. The contacts 58 and 58 are short and positioned directly opposite the middle of the co-o erating contacts 55 and- 62, in order that t ey may receive current` during the middle of the impulse wave in a d 'manner which is well known in the art.

We may now consider the indicating means by which the attendant at the receiving station determines the relative speedsl of the distributers at the transmitting and receiving stations.

alternate indicator contacts 70. Similarly, 13o j For the purpose of indicating therelative speeds, we employ lamps S and F, which are connected to lamp F is connected byA conductor 7l to the v intermediate indicator contacts 72. Before at the receiving station, are' being'driven by' their motors, then for the 'urpose 'ofV testingA synchronism, the. switc es 15z and '-15" at the transmitting' station are closed sogas to bring `the transmitting contacts 10 intocircuit. Then, with the contacts 1Q in their normal position, as we have seen, an alterl nating current -will besupplied to the line.

The 'receiving` ofthis .current by the line relay LR willcause its tongue- 52 to oscillate to and fro with the result that the tongue 54l of printing relay PRwill. partake of'likex movements. At the time this test isloeing` made,`the' switch 61 is open and, consequently the oscillations of tongue 54 of relay PR will regularly apply current from battery 63 torv conductor 56 and segmental contacts 55.

Then, when-brushj57 passes over these/cone tacts, itvwill' connect the same with indicator In some.vv

contacts and 72 successively. instances, dependent uponthe time the' incoming impulses are received'relative to the 'time thebrush '57 bridges ithese con tacts,the. lamps S and F will be connected e operation of these will vand Y Fgrlemains lighted; thenv bothare extinguished; then S is lighted and F remains incircut. T more clearly understood` upon reference to Fig. 5 wherein .seven circuit conditions vare] depicted.' In each of the diagrams thelines' 73 represent the currents impulses .which come 1n over the lineandfarefapplied to, vthe relays LIE/and PR.-"lndthe-irstl'fdia' gram the incoming impulses agree exactly l with the segments 55'. In other-words,. t`h first impulse begins to arrive justv a'sljthe brush first engages segment 55. Thi`s"--'means A that whilethe brush is passingl over. the

segment, current will be applied to it.) iThev extent of application of current is indicated" by shadingt at portion of the contact whic is receiving current.

Thus, if we leak at' the second diagram, we will see that the ust at the moment the e first segment 70. vThis means that the current will be applied while I impulse arrives brush is leaving t the brush passes over the shaded ortion the'contact 55 of thisdiagram. t will'b remembered that contacts 62 are disco` nected by reason ofthe open switch 6 and, consequently, even though thecunpulsey continues while the brush is passing over a portion of segment 62, as shown in 'the second' diagram, still no current flows through that segment because of its o en circuit co" ion. Similarly, in the ot 1er diagrams, duration of application of current to the segmental contacts. Now, with curren t g ,gf ap .1V

shaded portions indicate the` (sixth iagram, the current impulse still fur- 'are 'to'be extinguished and the lamp S Willbe V`the last to beextinguished. a

l the-receiving disling lied as shownin the first diagram, it will e seen that .a circuit will be completed through bothlam'ps S and F. In'the sec-y ,l j

onddiagram, only the lamp F will belightthe third diagram, We have the condition in which the limpulse of current beginsat the i :instant thefbrushfrst engagescontact 72.

Under' this conditiomthelamp F is alsovv lighted.l the'. fourth diagram, the im-i pulse of-.currentcoincides withf the segment 62, and as these, are disc onmfec'ted ,nocurrent is applied toA the "lampsand-both are extinguish'edf.- In the fifth diagram, the 'imulse again overlaps contact 55 and current is-sup lied to light .lamp S alone. Inthe ther overlapsf'the segment55, but'not se ment 72. v Again only lamp rS is lighted. n theseventh' diagraimthe incoming im ulse again coincides with segment 55,'an the first condition isrepea-ted, and both lamps S and -F are lighted. In the 4caseassumed, the

,impulsesfhave vbeen coming vin at a'given rate,` and the receivin distributer has been goingat a rate too astto match its con-, tacts 55;`with the incoming impulses. -This is indicated bythe fact that the lamp F is the Alast to go out. .y By reference to the diagrams `of Fig'. 5, it Willbe seen that both lamps are lighted;- then S is extinguished extinguished, and then both are, lighted. That lthe' receiving d istributer is tl'avelingA faster than'the, transmittin distributer is leirtifnguis ed.` When the receiving 1 disilluminated, the lamp F will be the iirst.

e mayfnow` consider ibuter motor G and the associate controlmechanism. H. This motor and Uits controlling mechanism are the same in .contruction and arrangement as in the cas`e`of y 1l further description, but foig convenience of ference-"fthe various partsfjaredesignated by'similar but primed characters. l,The

ribu'ter'is traveling slower -than the transi y KAniitting distributed then after both lamps- `h egmotor C and* its c ontrol mechanismjD. I,*ther'efore, be unnecessary ,to give-.a f

while `the;,receiver fork 45"A is the corrected i element. y' Iheadditional controlling means :.mitter -forkllis the correcting element for.' fork 45;' .include anf-electromagnet 7 4,

. ably structurally divided, one-half comprising Winding 83 and magneticfcore 84 lying above the tines of the fork 45, and the other half comprising the winding 85 and the magnetic core 86 lying below7 the tines of the fork.

These parts are so located that the polarfaces of the cores 84 and 86 come into elose proximity to the edges of the tines ofthe fork. A switch 87 and connections 88 serve to open and close a shunt around the resistance 75. The magnet 74 is normally under the control of the holding relay HR and operates when energized, to exert its influence upon the tines of the fork 45. This normal condition exists when the switch 82 occupies its left hand position. For the purpose of starting, itis desirable to supply the magnet 74 with continuous current,fand this is obtained when the switch 82 is moved to its right hand position. A further control of the `fork 45 is provided by an electromagnet 88 which is connected by conductor 89 to the 'resistance 90 of rheostat I, the arm 91 of which is connected to the liv'e pole of grounded battery 92. As shown more particularly in Figs. 6 and 7,the mag.

net 88 includes two windings 93, 94, mounted upon a U-shaped core 95, the ends of which are in line with the ends of the tines of the fork. The position of this magnet may be varied with reference to the'ends of the tines by means of an adjusting screw 96 which passes through a solid post 97. The screw 96 is threaded through a threaded opening in the post 97, and is suitably connected to the yoke 95, so that the latter may be shifted toand fro by turning the -screw 96. By this screw an approximate adjustment may be obtained by hand. A continuous adjustment is obtained electrically by varying the current flow through the windings of the magnet 88. The variable current flow is brought about by varying the position of the Irheostat arm 91. At this point it may be noted that this armis frictionally mounted upon its shaft 98 so that it maybe moved by hand by overcomingthe rictional resistance. When not operated by hand -it is rotated by its shaft 98, wh1ch` is connectedby a tramof gears99 to the shait 100 of the motor 101, which is supplied with current from supply mains 102, 103. The train of gearing 99 is such, that the arm 91 is driven-at a verylow speed. 1n

practice we have found that a ratio of 3000 to 1 between the shafts 100 and 98 gives satisfactory results. The motor 101 is under the same.

. it will be said relay. At all times current fiows l' l through the eld winding 104 in the same The path for this current may/fl l' direction. be traced .from supply main 102 through resistance 105, resistance 106, and the lield winding 104, to supply main 103. When the tongue 107 ofthe motor relay MR is in its right hand position, current will flow downward through the motor armature over a path which may be traced from main 102 through resistance 105, the motor armature, right hand ,contact 107, and field winding 104. to main 103. When the tongue 107 of relay MR is in its left hand posltion, then current will flow upward through' the armature of the motor over a path which may be traced from main 102 through left hand contact 107, the armature of the motor, resistance 106, and field Windl ing 104, to supply main 103. Thus we see that the receiving distributer .fork is under 4 the control of twol magnets which 'in turn are under thevcontrol of relays HR and MR, the former connecting its magnet 74 into circuit .intermittentl and the latter causing the current throughrits magnet 8 8 to vary continuously, either to cause a speeding up of the fork vibrations or a slowing down of;

' In this `connection it.may be noted that when either of these magnets is energized,

bration. A v

Ve may now refer to the correction of the receiving distributer. This is brought about through correcting segmental contacts upon the receiving ldistributer head which variously operate switching recting relay CR to bring about an opera` tion 'of relays HR and MR, to apply the correcting influences of the magnetsV 74 and 88. The correcting contacts upon the distributer head include a series ofcontacts 108 which are connected by conductor 109 through relay SR to clude a series of contacts 110 which are connected by conductor 111 to one side of a condenser. 112, the opposite side of the conrelay SR and corground. They also"in a magnetic flux is set up, and the veffect of this magneticflux upon the tines of the fork is to increase their rate of videnser being connectedby conductor 113 to the tongue 114 of relay SR. The correcting contacts 108 and 110 are connected to the ring contact 1 15 by a brush 116, and the con-` tact 115 isconnected by conductor 117 to the.

Y both segmentsfis the same in polarityno t' .'s reversed correction is made, 'but whenever the current during the passage of the brush over such a pair of contacts, correction is made. .Thus,'the energy vforfcorrecting is obtained from the Vsignal impulses' them-` .selves and 1an* extra correcting impulse 'is Anot required. The operation will be readily seenfif we assume a-case. Thus, if the correcting and correcteddistributers arerun.-

'ning in synchronism,

thenno :correction will be applied.rv In such'case',-- reversals will come between the pairs of correctingcontacts ,and

` atreversalwill not occur while thebrush isy at -any `other position. If we are sending asignal which requires the lirstfco'ntact 10 to bek 1n its -normal position, .the second contact 10 to be in its normal,v o'sition, the .third contact l1() to-be -iniits a ternatefposition, andthe v our-thjcont'act 10 to' be in its alternate posi,

vposition 'during therst impulse,

" hand position during-the secondV and third I the fourth impulse.'

` v116 is passing tion, then it will be seen that the tongue 52 of` relay. LR will .occupyjits left hand itsri'ght impulses', andl its vleft', hand position` during 1 As i there is 1 exact syntongue 52 of relay LR `closes` its left hand contact-` and thus 'applies j positive battery to the contacts. .LikewiseQfwhile thebrush Iover the second and thirdv pairs of correcting contacts 108, 110, lthe tongue 52 of relay LRwill apply negative battery to .those contacts, and again while l the brush passes. over the fourth. pair of contacts 108 and l110,-the tongue 52 will c apply positive vcurrents Yto thoseA contacts..

Now, the effect ofsuch application' of current to these correcting contacts can be readily seen. The' application of `ps )siti've current to the first contact' 108 will complete a circuit through conductor 109 and theY windings of switch relay SR to ground.

t This will' cause the tongue 114 of relay SR to `'remain in or move to its 'right hand position. The continued application ot positive current to the correcting contact 11-0 ofthe,

first pair vwill cause one side of condenser 112. to be charged with 'positive current.

' Charging the condenser in this (way will of currentthroug'h of correcting'relayl CR. The effect of negainduce a negative charge upon'the opposite side of the condenser, `resulting 'in a iiow the right hand winding tive.current in e ri ht hand winding is 'to cause tongue 1180 relay CR to remain in or move` its right hand position.v At this point it may benoted that the same effect will .be produced by the passage of positive vcurrent through the left hand winding.

Likewise, vpositive current through theright This .induces a opposite-side hand windin'gorne'gative current through 66, Contact 119, conductor .120, right hand contact 118, the right hand winding `of relay MR, and the right hand winding of relay HR toground. By reason of the four con-` tacts 119, this circuit may be completedfour vtimes for each revolutionofthe receiving distrilauteriI Consequently, correction is not applied immediately upon the finding of a conditionrequiring 4 correction, but only when a'contact 119 is brought into circuit.

In this instance the" closing of circuit of rellays-MR and HR has the effect of hold-` moving L A through the right hand windings fingfthe' tongues107 and 80 in or This ' the left' hand winding will` cause 'tongue l118 sov `them totheir-right hand positions. Inthe right handpo'sition of tongue 80, no. circuit is completed for .magnet "74 and,conse qluently, no correction is applied' through t iis magnet.; Vith tongue 10'( of relay MR in its right hand position,-the flow oi. current throughthe motor 101 is such asA to 'i rotatei the rheostat arm 91 in a direction t'o increase the amount'of 'resistance 90 in -.circuit and, therefore. reduce the `magnetic iux in electromagnet 88 and permit the fork 45 topslow downits vibration. Now, when we come to a consideration of the Asecond pairof correcting'conta'cts 108,110, wel iind under the assumption, thatthe second transmitter contactw-'lO is in its normal position, and thereforel relay LR is operated to move its tongue 52 to its ri'ghtvhand position to '117, ring' Contact 115, and brush 116, to the .second pairof contacts 1108, 110. The application of 'negative'. current to the con- -tact 108 of this pair causes a flow of current through conductor' 109 and the windings of relay SR. This iiow results in causing tongue 114` of the latter relay to move-to its left hand position. The application of' negative currentto the ,contact 110 ot the second pair results in charging the adjacent side of the condenser with a negative charge.

off' t evcondenser, and the `curlrent iowing v .of relay\CR andthe lefthand contact 114 at such' time, causes f tongue 118 of relay' CR to remain in its right hand position,

with the same eifect upon relays MR and HR- as just described. In other words, no, correction is applied -as a'result of this condition. Coming now to the third pair of applyV negative current 'through conductor .j

ositive charge .upon the j 12o through'the lefthand winding les contacts 108,'110,'we-ind the third trans mitter contactY 10 in its alternate position,v

pair, just dischar 3110 of t and the application of negative current to the correcting contacts 108 110 of the third as in the case of the second pair. The a plication of this current to contact 108 ofP this pair causes a flow of current through conductor 109 and the windings of rela SR, just as before, and the tongue 114 of t at relay remains in its left hand position. At lthis time, however, the condenser 112 is already charged and has not been ed since charged over the contact e second pair of contacts and, conse ently, there is no fiow of current for the/third impulse through the lefthand windiI ofrela CR. Again, the effect upon relays/ R an HR is the same as before described` and there is no correction applied. Coming now to the fourth impulse, we have positive current applied, according to our assumption, to the contacts108, 110 of the fourth pair of correcting contacts. The effect of this application of current upon relays SR, CR, MR, and. HR, is as described in connection with the first impulse, andthe first pair of correcting con- .tacts 108, 110. Again, there is no correction applied. From these considerations, it will be clear that so long as the reversals between impulses occur between the pairs of correctthe pairs o correcting vwill occur while' the contact of the next pair.

mg contacts, there is no application of a correcting influence. This condition will, of and corrected `distributers are yrunmng in s chronism, orso close thereto that a c ange of polarity between pulses occurs at the instant the brush 11,6 is pas'sin from the second contact of one pair tot e first we assume that thetwo distrib not in synchronism, then the olarity will not occur between contacts 108, 110, but brush 116 is-in enga ement with` one of these contacts. Thus, i it be assumed that we are transmitting the same signal as before, viz: The first impulse positive, the second and third negative, and the fourth positive, and that the change in polarity between the'rst impulse and the second impulse occurs at the t1me the brush is on contact 110 of the rst pair of correcting contacts, then we will see that the relays are operated to apply correction in a way not heretofore done. Under this assumption, the positive current supplied to contact 108 will energize relay SR to move its tongue 114 to its right hand position just If, now, uters are changea'n/ v vvas heretofore described. The application of positive current to ing contact 110 will ofthe condenser 112 maintaining the cont-act 118 in its right hand the samel course, exist only when the correcting position. The resulting application of current through the right hand -windings of advent of the second impulse. This means that while the tongue 114 of relay SR remains in its right hand position, the condenser 112 is charged negatively, and a posi tive current flows through the right hand winding of relay CR. This current, as above noted, causes tongue 118 to move to its left hand position. Therefore, as soon as brush 66 connects contact 119 to battery 68, there will be a flow of current through the left hand windings of relays MR and HR, with the resulting movement of the tongues 107 and to their left handzpositions. Tongue 80 will Aapply current from battery 8l through conductor '79,- and rheostat 77 to controlling magnet 74. This application of current w1ll set up a magnetic flux which will cause the speed of--the fork 45 to increase. This will tend to cause the motor G to increase its speed and, therefore, Ycause the brush 116 to catch up to the incoming impulses. This action of the fork is increased bythe reversal of connections of the motor 101 through tongue 107 of relay MR and, as a consequence, rheostat I is operated to gradually cut out circuit of magnet 88. This, `as before noted, has the .effect of increasing the speed of the fork. From what we have said itwill be seen that the motor speed will continueto' resistance 90 from the i their tongues to their right hand positions. I i

In such case the motor speed will be gradually reduced until, again, the condition just described is reached, whereupomthe same relays will be operated to initiate an increase in the motor speed. In this way the speed of the motor -G increases and decreases continuouslythrough'a given range. In practice, the parts are so adjusted that about half of the time the motor vis running fast, and the other half running slow. In this way a practical sync nism between the correct-A ing and correct d distributers is obtained.

e may now consider the adjustment of the ring of correcting contacts 108, `110. In practice, it is found necessary, due to characteristics of the instruments, to provide for a relative adjustment for the correcting contacts 108, 110, and the receiving contacts .58, 58. In some instances in the prior art, the signal 'receiving contacts have been adjusted relative to all the other contacts upon the receiving distributer head, but this arrangement required a new positioning-of the 1,7e4,sie

operating o r sixth pulse contacts, which resulted in objectionable operation. We find, on the other hand, that byadjusting the ring containing correcting contacts 108, 110, relative to the other contacts of the-distrib- .uter head, satisfactory resultsj may be obtained. In Figs. 2, 3 and 4, we have shown a Apreferred construction for bringing about this adjustment of these contacts. In those gures, the rings of contacts tare differently arranged than the diagram of Fig. 1. In the latter ligure, rings have been placed side by side'for convenience of illustration In thek structural figures the contacts are arl ranged as they' are in practice, and each brush spans two rings .of vcontacts and the brushesare positioned 120 degrees apart as clearly shown in'Fig. 2. In the preferred structure, all contacts except the correcting' contacts 108, 110 are mounted upon an insulating disc 124 which is suitably secured by bolts 125 and spacing washers 126 to the casing 127 which, in turn, is provided with a base 128 by which it may be Vsecured toV any suitable support. The correcting contacts 108, 110 are preferably securedto an linsulating ring 129 which closely fits upon the periphery of the disc 124. Shoulders upon the disc 124 and' the. ring 129 abut at 130 and prevent the outward withdrawal vof the ring from the disc. Spring tongues 131 are secured to the rear of the disc' 124 and `extend outward beyond the disc and into f engagement with the rear of the ring 12,9.

By this construction the ring 129 is held in place by a frictional engagement of the parts. Whenit is desired to adjust the ring 129 and the correcting contacts 108, 110 carried by it, it is only necessary to manually Grasp the handle 13 ace of the ring 129 by` any suitable means such as screws 133, and move the ring and its contacts against the Afriction of the parts until the ring is moved to its desired position, in accordance with the indication' of the left `hand-edge 121 of the handle' 132 upon a 'scale 134 marked upon the adjacent edge of the casing 127. .i y

Wve may now consider the operation briefly. With the apparatus in a condition of rest, the first step is to start the motors -atboth transmitting and receiving stations.

Inthe case of the motor C this is done, as before explained, by first closing switch 28 and bringing the motor up to speed by means of the rheostat 31. At `the same time the fork 45 is set in vibration and alternating current is supplied to the motor.` When the motor is operating satisfactoril the lamp 39 burns steadily. The motor is started in the same way. The next step is to close switches 15 and 15', so as to include the transmitter contacts in circuit. Thereupon, the rotation of the transmitting distributer '-.appliesa pure alternating current to the line.

which is secured to the distributer.

The next thing is to place each receiving distributer in phase with the distant transmitting distributer. To this end,` switches 61 .and 82 are opened. By the opening of the former, proper circuit conditions are established lfor the operation of the indicator lamps S and F. By the opening of the latter, control magnet 74 is prevented from operating. Magnet 88 is then adjusted until the receiving distributerruns slower than the transmitting distributer by a certain l'definite amount. This adjustment is obin circuit and the receiving distributer is adjusted to run faster thanithe transmitting distributer by ya certain definite amount.

In making this faster speed adjustment the switch 82 is moved to its right hand position and the rheostat-arm 7 Sis moved back and forth oyer resistance 76 until the desired vspeed difference is obtained. The fact that the receiving distributer runs faster than thev transmitting distributer is indicated by lamp F being last to go out. In this instance, the periodv is measured by observing the lightingsof one of the lamps just as before. Theoretically, the speed. dilference in both cases should be the same amount, and in a two channel system such as herein disclosed4 that difference maybe in the neighborhood of .3 R. P. M. With such an assumed speed difference, which is merely illustrative, the receiving distributer should run .3 R. P. M. slower than the transmitting distributer with magnet 74 out of circuit and .3 R.

P, M. faster than the transmitting distributer with magnet 74 in circuit. Measured by the interval between successive lamp lightings, this .3 R. P. M. would amount to 40 seconds. However, in practice, it is found that equal and opposite effects upon t-he receiving distributer cannot be had with speed differences of the same amount. We have found it necessary to reduce the speed difference when the receiving distributer is run slower than the transmitting distributer,`and to increase the samewhen the receiving distributer is run faster than the transmitting obtained by. running the receiving distributer Thus, good results havevbeen .1 R. P. M. slower than the transmitting disy tributer with a magnet 74v out of circuit and .5 R. P. M. faster with magnet 74 in circuit. The difference between the theoretical and iso practical values may be due to the difference in the action of magnet 74 when energized continuously, as it is when the above starting adjustments are being made, and when energized intermittently, as it is when adjustments are automatically made during the regular operation' of the system.

The next step in the operation is to find the letter. To this end switch 61 is closed and switch 82 is moved to its left hand position. Then the printers on all channels are turned on and the transmitting station is Y -requested to transmit 4some letter, as the letter. R, on one of the channels, say the first. If the printer on this channel prints the letterR continuously, while the other channel printers areat rest, the letter has 'beenfund; Iii'ca'sethis reslt's not had, then switch 82 is thrown to its right hand "position arid switch 87 is closed. This re-` sults in energizing correcting magnet 74 with `an abnormally heavy current which tends to make the fork 45 run considerably faster than usual. The result of this action of the f ork is to cause the receiving' distributer to gain rapidly upon the transmitting distributer until the two are'in proper phase rela-- tion, as is indicated b the printing of the letter R upon the tlst channel printer. When the letter is thus found, switch 82 is thrown to the left hand position and switch 87 is opened. This places the system in condition foroperation. During operation the .it may be pointed out that each is provided with weights to assist in determining accurately the rate of vibration. In practice the transmitting fork 45 has its weights 47 adjusted until it vibrates at a definite rate. In like manner the fork 45 is provided with\weights 47', and these are adjusted upon the fork until the latter vibrates at a somewhat less rate than the correcting fork 45. The adjustment of the magnet 88 causes the fork 45 to increase its rates but still leaves it below that of the correcting fork 45. Then when the correcting magnet 74 is brought into play, the

joint effect of the two magnets 74 and 88 is such as to cause the fork 45" to vibrate at a rate slightly in excess of that of the fork 45. As before noted, it is desirablev to operate the refteiving fork so that about fifty per cent of the time it will be running fast, and about fifty per cent of the time runnin slolw, relative to the fork 45 of the transmitting station.

Before concluding the description, it

CR, MR and HR are polarized and each will hold its tongue in that position to which it was last moved until current is received which will move it to th; opposite position. Relays LR and PR move their tongues to the lett upon the receipt of positive current and to the right upon .the receipt of negative current as indicated bythe positive and negative signs upon the drawing. Relay SR is operated by positive current to move its tongue to therlght andfby negative current to move its tongue to the left, as indicated. Relay CR moves its tongue to the right upon receipt of positive current in the left hand winding or negative current in the right hand winding asvindicated by the positive sign above the left 'hand winding, lthe negative sign above the right hand winding and the associated arrows pointing toward the right. The reverse movement is caused by negative current in the left hand windin orv positive current in the right hand-win ing as shown by the second row of signs and arrows. Relays MR and HR move their tongues to the left when current is received in the left hand windings and tothe right when current is received in the right hand windings.

Obviously the 'main line L may be a complete metallic line or a line having a ground return such as illustrated. Vhere the-latter is the case, the transmissionl current source must be grounded. This may be 'accomplished in various ways. As shownin Fig. 1, two electric generators 137 and 138 are connected in series circuit with the supply mains 11 and 12 and the ground is applied'between the generators at 139.

Throughout the drawing a number of batteries appear. In practice ordinarily but one source of current would be necessary at each station. This might be a battery or other current source. The batteries illustrated are merely illustrative of, sources of current supply and the many sources have been shown merely to simplify the diagram and to avoid rendering the same obscure or diilicult to' read.

By way of modification it may be' pointed out that correcting magnet 88 may be operated by hand and without using the motor 101 and associated rheostat I. In such case, the relay MR would have nouseful function and might be omitted. Where such a change is desired, the windings of magnet 88 are connected in circuit with a source of current, such' as the battery 136, as indicated in the diagram by the switch being thrown to its upper position. 'When the switch 135 is in its lower position the motor 101 and associated rheostat I are connected y in circuit to perform their functions as above explained. When the relay 88 is to be manually controlled, the screw 96 is used. By

`uters of other types than those employing segmental contacts and co-operating brushes may be employed. Thus We may locate pairs of contacts adjacent to each other and move them into and out of contact by means of a rotating drum, or other traveling membe further modi ber.

As previously pointed out, the system may in transmitting signals by radiant energy through the air, ether, or other` agency than a telegraph Wire.

Obviously too the tuning forks and 45 might be replaced by other vibrating members. However, :forks are ordiuarilypreferred because they can be properly operated when mounted on relatively light bases Whereas reeds and other similar vibrating members having only one vibrating element require a very rigid supporting base.

Other modifications will readily suggest themselves to persons skilled in the' art. In view of vthese obvious changes I, therefore, do not Wish to be limited to the specific matter herein disclosed, but aim to cover all such modifications by the terms of the appended claims'.

What-I claim and desire to secure by Letters Patentof the United States is 1. A system of the class describediiiluding means for transmitting signals cnrient variations, a distributer, a motor for driving said distributer, avibrating member and connections for controlling said motor, means responsive to said current variations' for exercising .control of said vibrating mem- Vber by intermittent .action1 andy means also responsive to said current variations for eX- ercising an .additional control of said vibrating member by a continuous variable action.V

2. A system of the class described including means for transmitting signals by. current variations, a distributer,` a motor for driving said distributer, a vibrating member and connectionsfor controlling said motor,

an electromagnet for controlling said vibrating member, a relay and connections responsive to said current variations to energizeand deenergize said electromagnet, a secondelectromagnet for controlling .said vibrating member, and means for continuously energizing said second electromagnet bya variable current.

3; A system of the class described included by adapting it for use lcorrected disti'ibuter to run slightly slower than the correcting distributer, and means responsive to impulses from the correcting distributer to operate said regulating means.

-to vary both said forces in the maintaining of'synchronous operation.

4. A system of the class described-including independently driven correcting and clorrected distributers, means for applying'two vcorrecting forces both operative to increase' or decrease the speed 'of the corrected distributer relative to that of the correcting distributer,-and means responsive to signaling impulses from the correcting distributer for varying both of said forces in the maintaining ofsynchroiious operation.

5. |lfhe combination of an electromagnetically operated vibrating member, means for varying the rate of vibration of said member byan intermittentl action and also by a continuously variable action. r

6. The combination of an electromagnetically operated vibrating member, an electromagnet for controlling the variations of said member, means for energizing said electromagnet intermittently, a second electromagnet for-controlling the vibrations of said member, and means for energizing said second electromagnet continuously by a more or l'ess fluctuating current.

7. A system of the class described includi ing means for transmitting signals by cur- 1 rent variations, a distributer, a motor for driving said distributer, a vibrating member and connections for controlling said-motor, two electromagnets for variably controlling the rate of vibration of said member, relay` means responsive to said current variations,

and means for causing said electromagnets to operate cumulatively for one condition only of said relay means.

8. A system of the class described including means :tor transmitting signals bycurrent variations, a distributer, a motor for driving said distributer, a vibrating member andconnections for controlling l said motor, l two electromagiiets for variably controlling the rate of vibration .of said member, relay means responsive to said current variations,

said relay means to cause said electromagnets tooperate cumulatively with a gradually increasing eect.v

9. A system of the class described includand means responsive to onecondition of i ing means for transmitting signals by current variations, a distributer, a motor for driving said distributer, a vibrating member and coni'ie'ctions` for controlling said motor,

ing means for transmitting signals by current variations, a distributei', a motor for driving said distributer, a vibrating member and connections for controlling said motor, two electromagnets for controlling said vif brating member, relay means responsive to said current variations, and means responsive to one condition of said relay means to cause said electromagnets to act cumulatively with a gradually increasing effect and responsive to another condition of said relay means .to cause the joint effect of said electromagnets to be less and gradually decreas-v ing.

' 11. tA system ofthe class described including means for transmitting signals by -current variations, a distributer,`a motor Afor l' driving said distributer, a. vibrating member. .and connections for controlling said motor,

two electromagnets for controlling said vibrating member, relay means responsive to said currentvariations, and means respon.- sive to one condition of said relay means to cause said electromagnets to act cumulatively with a gradually increasing effect and responsive to another' condition of' said relay'-4 means to cut one of said electromagnets out of circuit and cause the other to act with a gradually decreasing effect.

' said motor.

for actuating said arm.

12. The combination of a vibrating member, means for infiucncing tlie period of vibration of said member, an arm movable to andfro at a slow speed to control said influencing means, and a reversible motor 13. The combination of a vibrating member, electromagnetically controlled means for inuencing the period of vibration of said member, a rheostat included in circuit withl said means, a motor geared to the arm of said rheostat so as to move the same to and fro over the rheostat resistance at a slow speed, to vary the influence of said influencing means, and means for reversing 14:. The combination of a traveling member, means for infiuencing its speed of travel, and an arm continuously driven at a slow speed to control said infiuencing means.

15. The combination of a traveling member, means for influencing the speed of travel of said member, an arm movable to and fr o at a slow speed to control said influencing means, and a reversible motor for actuating said arm.

16. -The combination of a traveling member. electromagneticallv controlled means for infiuencing vthe speed of travel of said member, a rheostat included in circuit-.with said means, a motor geared to the arm of said rheostat so as to move the same to and fro Vover thev rheostatresistance at a slow speed to vary the influence of said infiuencing means, and means for reversing said motor. 17. A system of the class described 'including a conductor, means for transmitting signals over said conductor by current variations, a distributer, a motor for driv" said 'distributer, a. vibrating member iii-d connecti ns for controlling said motor, an electromagnet for controlling said vibrat- 8 ing member, a circuit for said electromagnet, a relay under the control of said con- 4ductor for controlling said circuit, a second I electromagnet for controlling said vibiai'tikng member, a. circuit for said second electro- `magnet, a variable resistance in said latter circuit, and means under the control of said relay for varying the amountv of said resistance included in said circuit.

18. A system of the class described including a conductor, means forA transmitting signals over said conductor by currentvari-- ations, a distributer, a motor for driving, said distributer, a vibrating member and connections for controllingv said motor, an electromagnet for controlling said vibrating member, means under control of said conductor for intermittently energizing said "electromagnet, a second electromagnet for controlling said vibrating member, a\

rheostat and current supply connected in circuit .with said second electromagnet, a motor geared to operate the rl'ieostat arm continuously at a verylow speed, and means under'control of said conductor for deter- 105 mining the direction of rotation of said motor and said rheostat arm. 19. A system of the class described including a conductor, means for transmitting signalsover said 'conductor'by current vari- 110 ations, a d istributer, a motor for driving said distributer, avibrating member for controlling sad motor, and means responsive to current variations in said conductor and continuously operative to gradually increase or gradually deci-ease tlie'rate of vibration of said member.-

20. A system of the class described including a conductor, means for transmitting signals over said conductor by current variations, a distributer, a motor for driving said. distributer, a -vibrating member for controlling said motor, an electromagnet for controlling the vibrations of said vil brating member, and means responsive to current variations in said conductor to continuously energize said electromagnet by a variable current.-

` 21. A system of the class Adescribed including a conductor, means for transmitting signals over said conductor by current variations, a distributer, a motor for driving said distributer, va vibrating member Jfor controlling said motor, an electromagnet for controlling the vibrations of said vibrating member, a resistance'adapted to ,be

included in circuit with said electromagnet, means for varying the resistance included in said circuit, and means responsive to current variations in said conductor to control said resistance varying means.

, 22. A cluding a conductor, means for transmitting v signals over said conductor by current variations, a distributer, a motor for driving said distributer, a vibrating member for controlling said motor, an'electromagnet for controlling the vibrations of. said vibra- 'responsive to current variations in said conductor, and means operative in one position. 'of said relay to gradually increase the speed of said vibrating member and in another position of said relay to gradually decrease the speed of said vibrating' member.

24. A system of the `class described including a conductor, means `for transmitting signals over said conductor by varying current impulses` according Vto. combinations of a code having the same number'of timeA iii-. tervals for each s1gnal,a receiving distrib-...- uter having passive correcting contacts and traveling means for successivel closing circuit with said contacts,` an e ectric motor for driving said distributer, means Jr`or regulating the motor speed so that-the distance traveled by said traveling means during each time interval of .the signal shallap-v proximate that required to close circuit with two correcting contacts, controlling meansv actingcontinuously upon said motor and tending to vary its speed, and means dej pendent upon the electrical condition of said correcting contacts to vary the operation of said controllingmeans.

25. A system of the class described including a conductor, means for transmitting signals over said conductor by varying cui'- rent impulses according tocombinations of a code having the same number of time intervals for each signal, a receiving k"distrib- 'titer-having passive connecting contacts and traveling means for successively closing cirsystem of the class described'in-- means cuit with said contacts, an electric motor for driving said distributer, means for regulating the motor speed so that the distance traveled by saidv traveling means during each time interval of the signal shall approximate that required to close circuit with two correcting contacts, additional means for further controlling the motor speed, an

velectromagnet i for controlling said additional means', a rheostat and source of'current in circuitI with said electromagnet, a motor for driving the rheostat arm to and fro continuously at avery low speed, means for reversing said latter motoigand means ,dependent upon the electrical condition of said correcting contact to cause the operation of said reversing means.

.26. A -system of the. class described including transmitting and receiving distrib- ,uters, means for sending signals from the 'former'distributer to the latter by varying current impulses according to a code having the same number of time intervalsfor each.,.signal, electric motors for driving said distributers, means for driving said motors at approximately the same speed,and means for maintaining synchronism between said distributers including means independent of said drivinfir means for continuously acting Vupon the eceiving motor and tending to change its speed and vmeans dependent upon the energy of the signal im ulses themselves ,to Varyv the operation o means.

27.. A system.' kof the class describedl .in-

Acluding'transmitting and receiving distributersmeans for sending signals from the former distributer to the latter `by var .ing

ingv the same number of' time intervalsfor 4each signal, electric motors 'for driving said distributers, means for bringing said motors said vcliianging ice current impulses according to a code avupto approximately the same speed, and

or. .maintaining synchronism 'betweenysaid distributers including additional vmeans for further controlling the receiving motor speed, an electromagnet for controlling said additional means, .a rheostatand source of current in circuit with said electromagnet, a motor for driving the rheostat armto 'and ro at a very low speed, means fof-reversing saidilatter motor, and means dependent 'upon the energy of the signal impulses themselves to cause the operation y of'said-reversingm'eans. 2S-A system of. the class described including independently driven correcting and v corrected distributers, means located'at the corrected distributer and controlled by impulses `rom ythe lcorrecting distributenior determining the relative speeds of said dis-l tributers, two adjustable :regulating means operable in. .one condition to cause". the corrected distributery to run slightl faster than -the' correctingi'distributer an :fin another condition to cause the corrected distributer to run slightly slower than the correct-ing distributer, and means responsive to imulses from the correcting distributer to ad- ]ust both said regulating means to maintain synchronism between said distributers.

29. A system of the class described including independently driven correcting and corrected distributors, two electric speed indicators, separate contact means controlled respectively by the corrected distributor and by impulses from the correcting distributor and co-operating to energize said electric indicators simultaneously but in different recting distributer and in'- another way when it runs slower, and means for adjusting the .speed of the corrected distributer td correspond with the speed of the correcting distributer. n ,f

31. A system of the class. described including independently 'driven correcting and corrected distributers, the latter having two series of contacts, an'electric signal in circuit with alternate contacts of one of said series, a second electric signal in circuit with the intermediate contacts of the same series, means for applying to the contacts of. the other of said series current impulses received from the correctin distributer, traveling means for electrical y connecting contacts of the two series, and means for driving said traveling means whereby. the relative speeds ofsaid distributers will be made known by said signals.

32. A system of the class described including independently driven correcting and corrected distributers, the latter having two series of contacts, each contact o the second series being adapted to engage two' con- '33. A system of the class described including independently driven correcting and corrected distributers, the latter having alternate indicatorv and signal contactsarranged in a series and traveling means for successively closing circuit with said contacts, in-

the latter having two series of contacts, one

series consisting of-alternate signal and indicator contacts, a `series of signal receiving elements connected to said signal contacts respectively, an indicator connected to alternate indicator contacts, a second 4indicator connected to the intermediate indicator con-- tacts, one electrical connection to alternate contacts of the second series,"another electrical connection to the intermediate contacts of the second series, means for applying impulses received from the correcting distributer to,v said electrical connections, means for interrupting one of said electrical connections while determining the relative speeds of said distributers by said indicators, and traveling means for electrically connecting contacts of the two series. e

`35. A system of the class described including 'a conductor, a receiving distributer having a series of correcting contacts and a series ofsignal-receiving contacts, the latter followed by an operating contact having a permanent positionalrelation to said signal receiving? contacts, means for transmitting code signals over said conductor., each ,signal having time intervals corresponding in number toi said signal-receiving contacts, a mo'tor fordriving said' distributer, means dependent upon said correcting contacts and 'upon energy :received from the signal impulses themselves to vary the motor speed, and means for adjusting said correcting contacts as a whole relative to said signal-receiving and operating contacts as a whole.

36,'A system of the class described inf' cluding independently drigen correcting and corrected distributers, 'the latter having a series of correcting contacts and a series of signal-receiving contacts followed by an operating contact having a permanent positional relation to said signal-receiving con.

tacts, means-dependent upon said correcting l contacts and uponk the energy of the impulses constituting the signals to vary the speed of the corrected distributer, and means for adjusting said correcting contacts relative to said signal receiving and operating contacts. t f

37. A systemv of the cla-ss described including transmitting and receiving distrib- 'change the relative uters eachhaving a plurality of channels` driving means for said distributers, a set-` of transmittingI contacts for-each channel,v

connecting and current supply .means for said contacts vvhereby when running idly an alternating current is 'current to change the relative speeds of said distributers, indicators, means for modi- :tying said normal current, and means responsive to said modified current .to-operate' said ,indicators to indicate the relative speeds of said distributers. v

38. A system of the class.1 described in-l cluding rtransmitting and `receiving distrib'- uters each having a plurality of channels, driving means for said distributers, a .set

of code'signal transmitting contacts-for each providefa ciirreiit'- 'having regular polarity .1 said .indicators Vdriving means for .saidfdistributei's,"aset of ,transmitting clicts for leach channel,

-orrectms and Cin-trent.Supply-.hierims-fOr-Seidv oli'aa'as :and a rotary member' `for.=r'1i`gg-'H1gone. of saidl receiving -contacts and succes-j` f sivel'y engaging two-'correcting contacts dui aline-1 v're/1237 and djusti-ng. evices V:for said rotary member-controlled by the `joint operatiomofsaid -line relay and said .corre'cting" contacts, said correcting devic` actin to a 1 "and removea correction o .Stem-Geref g" ppy Pnsmg mdependently dr-Wenv' 'Quinn-t.' m fiiitrvals. during Anormal operation, and said adjusting'device l,acting response to ab..`

'-'mal current, and speedI indica ingnie'ansije sponsive to'said modlied current;

: changes, indicators, andiineans for operating uter's each having a pluralityA .of g. channels,

contacts -whereby when yfrunnir'i idly .plural reversals of polarity occurzin't nals being transmitted through each-channel; correcting means responsive'toksuclnormal current to change the relativ 'speedsfo'f said distributers', ,means forfinodl ing-fSaidQ-.nor-Q 40. A vsynchronous telegraph sy pulse sending and receiving distributors,

operatingelectric motors therefor", finde#A pendent vibrating members for'-"applyingvperiodically varying, correcting current to the windings of `said motors vrespectively to determine the lspeeds of saiddistributors,

Hadjustable means independent-of said vibrate ing members for driving the'motors 'atapi proximately the speedsofg-the.corresponding members, andelectroemagnetic ycorrect-j,l ing means responsive ,to "im vuflses imparted* by tliejseiiding distributorl o r varying the speed of the vibrating-member of the fre ceivin distributor..

transmitted through the .transmitting distributer, c or recting means 'responsive to said alternatingv g'respc'ilise tcigsai modified@ L-curient... i. ,7'2" 39. A system of the class described-"ini clulding` transmitting [and receiving distribf 1 .af varying @tiene Sigsepakratecorrecting.- and a synchronous 'telegraph `ilsysteni,

independently driven, current. impulse sending and receiving distributors, an electric motor for operating .said receiving distributrolled by impulses imparted by the sending distributor for varying the frequency of said vibrating member.'v

42. 'In a synchronous telegraph system, independently driven, current impulse send ing and receiving distributors, operating electric motors therefor, independent electro-magnetically operated tuning forks for ysupplying alternating correcting current'to *windings of said motors respectively, ad-

'.justable meansindependent Vofsaid forks for dri.,vin,'g" the motors at approximately the #speeds of the respective forks and-correcting devices controlled by impulses imparted [the vsending distributor for .varying the speed'fo the re'ceivin distributor fork.

AgfAsystem of t e-clas'sfdescribed including independentlydriven correcting'and corrected distributors, -yibratin members fori determining-the speeds of sai distributors, means-Fier? apply-ins tivo .tvrretni-iorcs-t0 vary-the/,s'peed of'vibrating v erjof the `corrected. distributor relative .1.

, 59.5 hat'fofthe correcting distributor, "andlmeans' responsive tof impulses .from V the. correcting distributor y both'offsadjforces 'inthe maini tainiiigfof.isfynchlonousoperation.;v li c 'In a synchronous' telegraph system loyng a definite interval signal code, send-' v ing each-l signal interval,

predetermined value-at substantially regular ing; and .receiving distributors, the' receiving l distributqrhaving receiving andcorrecting f Anormal conditions-tOI-gradually increase or decreasethe speed...of saidrotary member. 45; In a synchronous telegraph system, the' combination with independently driven correcting and corrected distributors and vie-fbr'atory members for determining the speed of` saidv distributors, of `interniittently acting j correcting jmeansv for .applying a vcorrection of predetermined valueto the corrected disber associated with the corrected distributor, said correctingand adjusting means beizc ing automatically responsive tovariations in the speeds nf said distributors.

46. In a synchronous telegraph system, in

dependently'driven correcting and corrected distributors, vibrating members for respectively determining 'the speeds of said distributors and correcting and adjusting devices for the vibrating member of the corrected distributor and automatically controlled by the difference in speeds of said distributors, said correcting device being arranged to periodically increase or decrease the speed of the vibrating member lby a definite amount and said adjusting device vbeingl arranged to gradually vary the speed fof t e vibrating member through a considerable range.

, In a synchronous-telegraph system, in-

f dependently driven correcting and corrected 20 distributors, vibrating members for respectively determining the speeds of said distributors, correcting andadjusting magnets applied to the vibrating member of the corrected distributor, means for intermittently energizing the correcting magnet to increasev or decrease the speed of the distributor by a definite amount and means for gradually varying the flow of current through; the l,adjusting magnet to correspondingly vary the speed of the vibrating member through a considerable range.

48, In a synchronous telegraph systemA correcting and corrected distributors, two,

indicating electric signals associated with the corrected distributor, contact means controlled by impulses receivedfrom the correcting distributor for simultaneously open ing and closing the circuits of both of said signals and meanscontrolled by the corrected distributor for alternately and at regular` intervals o ening and closing the circuits of said signa s, whereby both of said signals operate successively in one order when the speed of the corrected distributor is faster t an that of the correcting distributor and in reverse order when the speed Lof the corrected distributor is slower.

49. In a synchronous telegrph system, sending and receiving current impulse distributors, a motor for driving said receiving distributor, a vibrating member for determining the speed of said motor, an; electroinagnet for adjusting the rate of vibration of said member, a rheostat interposed in the f ,1 energizing circuit of said electro-magnet, an

auxiliary control motor having speed reducarf gear connections with the arm of said estat and means responsive to abnormal tions in the speeds of said distributors ir determining the direction of rotation of said motor and the rheostat arm operated tnercby.

50. In a synchronous telegraph system employing a definiteinterval signal code, sending and receiving distributors, the receiving distributor ,having receiving and correcting contacts and a'rotary member for successively engaging said contacts, an electric motor for driving said rotary member,

`means.for regulating the m'otor speed so employing a definite interval signal code,

sending andreceiving distributors, the receiving distrlbutor having separater sets of code receiving and speed indicating contacts,` and a rotary member for successively operating said indicating contacts at regular intervals proportional to the signal intervals, a line relay and two indicators controlled jointly by said indicating contacts and said line relay and thereby operated intermittently and-successively in one order when the speed of the receiving distributor is faster than that of the sending distributor and in reverse order when'the speed of the receiving distributor is slower;

HOWARD L.

JOHN O. CARR. 

